Interfaces and Connectors
EBX-11 Reference manual
31
Serial Ports
The EBX-11 features four on-board 16550-based serial channels located at standard PC I/O
addresses. COM1 and COM2 are RS-232 (115.2K baud) serial ports. IRQ lines are chosen in
CMOS Setup.
COM3 and COM4 can be operated in RS-232 or RS-422 mode. Additional non-standard baud
rates are also available (programmable in the normal baud registers) of up to 460k baud. IRQ
lines are chosen in the CMOS Setup.
Each COM port can be independently enabled or disabled in CMOS Setup.
COM
P
ORT
C
ONFIGURATION
There are no configuration jumpers for COM1 and COM2 since they only operate in RS-232
mode. Use CMOS Setup to select between RS-232 and RS-422 operating modes for COM3 and
COM4.
Jumper V1[1-2] is used to enable the RS-422 termination resistor for COM3. Jumper V1[3-4] is
used to enable the RS-422 termination resistor for COM4. The termination resistor should be
enabled for RS-422 endpoint station. It should be disabled for RS-232.
StockCheck.com